Detection module for monitoring failure of fastening device, fastening system and monitoring method

Abstract

The invention relates to a detection module for monitoring the failure of a fastening device, the fastening device comprises a fastening rod (1), a fastening piece (2) and a fastening head (3), the fastening piece (2) and the fastening head (3) are arranged on the fastening rod (1) in a sleeving mode, and the detection module is characterized by comprising a cavity (4) capable of being elastically compressed, a chamber (4) provided for pressing against a radial plane of the fastener (2) around an axial section of the fastener (2), the chamber (4) being filled with a fluid; and a pressure sensor (8) in communication with the fluid in the chamber (4) for detecting the pressure of the fluid. The invention also relates to a method for monitoring the failure of a fastening device by using the detection module according to the invention and a fastening system. The fastening system comprises the fastening device and the detection module according to the invention.

Description

Technical Field

[0001] The present invention relates to a detection module for monitoring the failure of fastening devices, a fastening system, and a method for monitoring the failure of fastening devices. Background Art

[0002] Fastening devices are widely used in engineering, such as construction engineering, pipeline engineering, mechanical engineering, electrical engineering, and so on. Generally, fastening devices are used to fasten different components together or anchor components to building structures, such as concrete, so as to achieve the purpose of fixation. The stability of fastening devices is closely related to engineering safety. Once the fastening device breaks and falls off, it may cause huge personal and property losses. Therefore, it is of great significance to monitor the failure of fastening devices.

[0003] Traditionally, the monitoring of fastening devices mostly adopts the method of manual inspection. In manual inspection, a torque wrench is usually used to test the tightness of fastening devices one by one or visually inspect the preset paint marks, which results in low detection efficiency, requires the installation position of the fastening device, and cannot detect the failure signs in time.

[0004] In the prior art, there are also solutions that directly monitor the stress or strain in the fastening device using sensors. In these solutions, the sensors need to be directly placed in the fastening device and bear the fastening force of the fastening device, which poses high requirements on the sensors and is prone to malfunction due to excessive fastening force.

[0005] Therefore, there is an urgent need for a solution that can reliably monitor the failure of fastening devices, in which the sensors used do not have to bear the fastening force of the fastening devices. Summary of the Invention

[0006] The object of the present invention is to provide a detection module for monitoring the failure of fastening devices, a fastening system, and a method for monitoring the failure of fastening devices, in which the sensors used do not have to bear the fastening force of the fastening devices, and the detection module and the fastening system can be simply realized as a whole, have high reliability, and are widely applicable to various application scenarios of fastening devices, without being restricted and affected by construction conditions, installation environments, etc.

[0007] In the scope of the present invention, fastening devices relate to various fastening devices for connecting different components together or fastening components to a mounting surface. The fastening device should include a fastening rod and a fastener and a fastening head sleeved on the fastening rod. Here, the fastening rod is used to be inserted into a hole in the component or mounting surface to be connected, and the fastening head is used to lock the fastening rod. Exemplarily, the fastening rod may include bolts, studs, screws, self-tapping screws, wood screws, pins, rivets, welding studs, among which bolts especially include ordinary bolts, high-strength bolts, anchor bolts, expansion bolts, chemical anchor bolts, stud bolts, etc.; the fastening head may be a nut or a screw cap, for example. In addition, the mounting surface may relate to the surface of a building structure, such as the surfaces of walls, columns, beams, etc. of tunnels, bridges, buildings, etc.; the surface of mechanical equipment components; the fastening surface of pipe flanges, and so on.

[0008] A first aspect of the present invention relates to a detection module for monitoring the failure of a fastening device, wherein the fastening device includes a fastening rod and a fastener and a fastening head sleeved on the fastening rod, and the detection module includes:

[0009] An elastically compressible chamber, the chamber being arranged to press against a radial plane of the fastener around an axial section of the fastener, and a fluid is filled in the chamber; and

[0010] A pressure sensor, the pressure sensor being in communication with the fluid in the chamber for detecting the fluid pressure.

[0011] According to the detection module proposed by the present invention, an elastically compressible chamber is arranged in a fastening device, and whether the fastening device fails is monitored through the fluid in the chamber. And due to the connectivity of the fluid, the pressure sensor for detecting the fluid pressure does not have to bear the fastening force in the fastening device. Specifically, in the detection module, an elastically compressible chamber filled with fluid is arranged around the axial section of the fastener and can be pressed against the radial plane of the fastener. This means that the chamber annularly surrounds the fastening rod and the fastener. And when the fastening device is locked, the chamber is pressed in the fastening device, such as between the radial plane provided by the fastener and another component or the mounting surface. And the chamber undergoes a compressive deformation relative to its initial shape based on its elasticity. This compressive deformation of the chamber will cause the volume of the chamber to decrease, which results in an increase in the pressure of the fluid therein. Once the fastening device fails, the fastener moves away from the adjacent component or mounting surface, which causes the chamber to be able to recover towards its initial shape based on its elasticity, which causes the volume of the chamber to become larger, thereby resulting in a decrease in the pressure of the fluid therein. Thus, whether the fastening device fails can be monitored by detecting the pressure of the fluid. In the present invention, in order to detect the pressure of the fluid, the pressure sensor only needs to be connected to the fluid in the chamber. Thus, due to the connectivity of the fluid, the pressure sensor for detecting the fluid pressure does not need to be in the force flow of the fastening device and does not have to bear the fastening force in the fastening device. In this way, the electrical part and the mechanical part of the detection module can be functionally decoupled, ensuring the safety of the easily damaged pressure sensor. Moreover, by means of the axial section surrounded by the chamber providing a stop in the axial direction for the chamber, the detection module as a whole does not have to bear the fastening force of the fastening device, and it is also ensured that the chamber will not be overloaded due to the fastening force of the fastening device when the fastening device is locked. And because of the fluidity of the fluid, even when only one side of the fastening device becomes loose and causes unilateral deformation, the detection module can also determine whether the fastening device fails based on the pressure change detected at this time due to the deformation of the chamber.

[0012] The present invention innovatively abandons the direct detection of stress or strain in the fastening device and instead uses a relatively indirect detection method to reliably monitor the failure of the fastening device. The present invention determines the failure of the fastening device through simple devices, without using a sensor with a complex structure to detect the stress or strain of the fastening device, nor does the detection module have to bear the fastening force of the fastening device, and there is no high requirement for machining accuracy. Moreover, the detection module realized by the pressure sensor for detecting fluid pressure has high reliability and good responsiveness, and can be widely applied to various application scenarios of fastening devices without being restricted and affected by construction conditions, installation environments, etc.

[0013] It should be particularly noted that the elastically compressible chamber used in the present invention can have various possible shapes. In order for the chamber to surround the axial section of the fastener and be pressed against the radial plane of the fastener, on the one hand, the chamber needs to be empty in the middle so as to be sleeved on the outer periphery of the axial section of the fastener; on the other hand, the chamber needs to extend along the radial plane of the fastener so that it can abut against the radial plane of the fastener when being pressed. Herein, "surrounding the axial section of the fastener" should be understood as surrounding or encircling at least partially, particularly mostly, and particularly preferably circumferentially, the axial section of the fastener. Exemplarily, in a top view, the chamber can be configured as an annular shape, a sector-annular shape, an elliptical-annular shape, a quadrilateral with a hole in the center, and so on.

[0014] It should also be noted that the elastically compressible chamber used in the present invention means that the chamber can be compressed under an external force and correspondingly partially or completely restore its shape when the external force decreases or disappears. Herein, the elastic compressibility of the chamber can be provided by part or all of the chamber material. This means that the chamber can either be partially made of an elastic material or entirely made of an elastic material.

[0015] According to an embodiment of the present invention, the fluid can be a gas or a liquid. In particular, the gas can be air, and the liquid can be oil. Herein, since gases and liquids have different compressibilities, the filled fluid can be selected according to factors such as the installation environment of the fastening device, the size or rated deformation amount of the chamber, and the type of the pressure sensor.

[0016] According to an embodiment of the present invention, the volume of the chamber shrinks relative to the initial volume when the fastening device is locked, and at least partially restores when the fastening device fails. Herein, the initial volume of the chamber can be understood as the volume of the elastically compressible chamber in a free state.

[0017] According to an embodiment of the present invention, when the fastening device is locked, the chamber deforms as a whole, deforms in partial directions, or deforms on at least one wall. Under the action of the fastening device, the reduction of the volume of the chamber can have various forms. Exemplarily, the chamber can deform as a whole, for example, being flattened from a circular-ring-shaped radial cross-section to an elliptical-ring-shaped radial cross-section; the chamber can only deform in partial directions, for example, only shortening the axial length while keeping the radial area unchanged; or the chamber can deform on at least one surface, for example, one or more surfaces of the chamber are recessed into the chamber interior. For these deformation modes, it is not required that the chamber is entirely made of an elastic material, but it can also be partially made of a rigid material.

[0018] According to an embodiment of the present invention, the radial cross-section of the chamber can be generally annular, elliptical annular or box-shaped. Preferably, the axial sidewall of the chamber can be configured with one or more corrugations or wrinkles. Here, by constructing one or more corrugations or wrinkles on the axial sidewall of the chamber, on the one hand, it can promote the elastic compressibility of the chamber in the axial direction, and on the other hand, it can define the deformation direction of the chamber and thus reduce its expansion in the radial direction, which helps to increase the pressure change amount of the fluid when the fastening device fails.

[0019] According to an embodiment of the present invention, the radial top surface and / or the radial bottom surface of the chamber with a box-shaped radial cross-section can be configured as elastic surfaces. In this embodiment, an elastic surface means that it can be recessed into the chamber when subjected to pressure, so that the volume of the chamber is reduced. In order to deform the elastic surface, corresponding protrusions can be constructed on the fastener and / or gasket of the fastening device. In particular, the remaining part of the chamber with a box-shaped radial cross-section can be configured as rigid. This rigid structure enables the chamber to deform only in partial directions or enables the chamber to deform only on one or two surfaces, such as being recessed into the chamber. Advantageously, the remaining part can be integrated with the fastener. This can reduce the number of components of the detection module and the fastening system and can effectively simplify the assembly.

[0020] According to an embodiment of the present invention, a spring compressed in the axial direction can be provided in the chamber. Through this embodiment, it can be particularly advantageous to assist the chamber to restore its initial shape in the case of the failure of the fastening device, so that the detection module can particularly reliably monitor the failures caused by the loosening, thread stripping, creep elongation of the fastening device itself and the material deformation of the mounting surface fastened by the fastening device.

[0021] According to an embodiment of the present invention, the chamber can be made of metal, rubber and / or plastic, wherein different materials among metal, rubber and plastic are preferably connected by pressing, welding, two-color injection molding or insert injection molding. Considering the simplicity of manufacturing, the chamber can preferably be made of plastic and formed by blow molding or injection molding. When using two or more materials to manufacture the chamber, in order to form a fluid-tight connection between different materials, pressing, welding, especially ultrasonic welding or fusion welding, two-color injection molding or insert injection molding can be used. For example, two-color injection molding or ultrasonic welding can be used to connect one plastic with another plastic or to connect plastic with rubber; or insert injection molding can be used to connect metal with plastic or metal with rubber.

[0022] According to an embodiment of the present invention, the pressure sensor is arranged on the circuit board.

[0023] According to an embodiment of the present invention, the circuit board can be separated from the chamber, and the chamber is communicated with the pressure sensor via a connecting pipe. Here, the circuit board together with the pressure sensor can be arbitrarily arranged by using the connecting pipe, especially to keep the circuit board together with the pressure sensor away from the operating area of the fastening device.

[0024] According to an embodiment of the present invention, the circuit board together with its pressure sensor can be integrated with the chamber. Through this embodiment, an integrated structure of the detection module can be achieved, and the assembly operation of the detection module on the fastening device can be simplified.

[0025] According to an embodiment of the present invention, the compartment communicated with the chamber is sealed by means of the potting part on the circuit board. In this embodiment, the fluid seal of the detection module can be realized by using the conventional processing method of the circuit board without customizing special seals.

[0026] According to an embodiment of the present invention, one or more of the following can also be provided on the circuit board:

[0027] A signal processing unit, which is signal-connected to the pressure sensor to analyze and process the pressure signal of the pressure sensor and determine the failure of the fastening device when a fluid pressure change is determined;

[0028] An alarm unit, especially a sound and / or light alarm unit;

[0029] A communication unit, preferably a wireless communication unit;

[0030] A power supply unit, which is preferably powered by a dry battery or a storage battery;

[0031] An energy harvesting unit, which is preferably a solar harvesting unit, a wind energy harvesting unit, a thermal energy harvesting unit, a fluid kinetic energy harvesting unit or an electromagnetic energy harvesting unit;

[0032] A wake-up unit, which preferably activates the detection module intermittently or in response to an external radio frequency signal.

[0033] Among them, the signal processing unit can perform a comparison between the current pressure and the initial pressure when the fastening device is locked, so as to determine the failure of the fastening device when the pressure decreases, especially when the decrease exceeds a predetermined threshold. For this purpose, the signal processing unit can include, for example, a memory, an AD converter, a comparator, an amplifier, an integrator and / or a differentiator, etc., so as to analyze and process the detected pressure signal, such as storage, analog-to-digital conversion, comparison, amplification, integration or differentiation, etc., and can also additionally provide information about the degree of failure, the speed of failure progress, etc.

[0034] According to an embodiment of the present invention, the pressure sensor may be a MEMS pressure sensor; and / or the pressure sensor may be provided with a temperature compensation device. For the miniaturization of the detection module, it is advantageously possible to use a MEMS pressure sensor. And in order to make the detection module applicable to an installation environment with drastic temperature changes, it is preferably provided with a temperature compensation device for the pressure sensor to reduce or avoid the influence on the detection module caused by the pressure fluctuation caused by temperature changes.

[0035] The second aspect of the present invention relates to a method for monitoring the failure of a fastening device by using the detection module according to the present invention.

[0036] The third aspect of the present invention relates to a fastening system, which includes a fastening device and the detection module according to the previous aspect of the present invention, wherein the fastening device includes a fastening rod and a fastener and a fastening head sleeved on the fastening rod.

[0037] The detection module according to the present invention and the fastening device are jointly provided in the fastening system according to the present invention to provide a simple, highly reliable and widely applicable monitoring means for the failure of the fastening device. Here, the fastening rod may include bolts, studs, screws, self-tapping screws, wood screws, pins, rivets, welding nails, among which bolts especially include ordinary bolts, high-strength bolts, anchor bolts, expansion bolts, chemical anchor bolts, stud nails, etc.; the fastening head may be a nut or a screw nut, for example.

[0038] According to an embodiment of the present invention, the radial cross-section of the fastener is configured as an L shape; or the fastener is composed of a straight sleeve and a gasket. Here, the fastener providing support for the chamber of the detection module may be constructed integrally or separately. The integral fastener may have a shape similar to a flange sleeve or a sleeve with a flange, which includes an axially smaller-diameter section and a radially larger-diameter plane for providing axial stop and radial support for the chamber respectively. The split fastener may include a straight sleeve and a gasket that can abut against one end of the straight sleeve, whereby the split fastener can also provide an L-shaped radial cross-section and can also provide axial stop and radial support for the chamber.

[0039] According to an embodiment of the present invention, the detection module is assembled between the installation surface fastened by the fastening device and the fastener; or the detection module is assembled between the fastener and another gasket. Here, the installation surface may relate to the surface of a building structure, such as the surfaces of walls, columns, beams, etc. of tunnels, bridges, buildings, etc.; the surface of mechanical equipment components; the fastening surface of a pipe flange, etc.

[0040] According to an embodiment of the present invention, an elastic washer or a corrugated washer is supported between the fastener and the mounting surface or the other washer. The elastic washer or the corrugated washer can particularly advantageously ensure that when the fastening device fails, the fastener is separated from the mounting surface or the other washer, creating space for the chamber of the detection module to return to its initial shape, so that the detection module can particularly reliably monitor failures caused by the loosening, thread stripping, creep elongation of the fastening device itself, and the material deformation of the mounting surface fastened by the fastening device.

[0041] According to an embodiment of the present invention, the fastener and / or the other washer may be configured with protrusions. Here, the protrusions can particularly correspond to the elastic surface of the chamber of the detection module, so as to act on the elastic surface when the fastening device is locked to make the elastic surface recess into the chamber.

[0042] According to an embodiment of the present invention, the detection module can be connected to the fastener and / or the other washer. Such a connection can further simplify the assembly of the detection module and avoid damage to the detection module during delivery, transportation or assembly.

[0043] It should be noted that the features, functions, effects and advantages, etc. according to one aspect of the present invention can also be referred to the above descriptions of other aspects of the present invention. In addition, the various aspects described in the present invention can be combined with each other in various ways. Description of the Drawings

[0044] Figure 1 A schematic cross-sectional view showing a detection module according to a first embodiment of the present invention;

[0045] Figure 2 A schematic top view showing a detection module according to a first embodiment of the present invention;

[0046] Figure 3 A schematic cross-sectional view showing the detection module according to the first embodiment of the present invention when the fastening device is locked;

[0047] Figure 4 A schematic cross-sectional view showing the detection module according to the first embodiment of the present invention when the fastening device fails;

[0048] Figure 5 A schematic top view showing a detection module according to a variant of the first embodiment of the present invention;

[0049] Figure 6 A schematic top view showing another variant of the detection module according to the first embodiment of the present invention;

[0050] Figure 7Schematic cross-sectional view showing a detection module according to a second embodiment of the present invention;

[0051] Figure 8 Cutaway perspective view showing a detection module according to a second embodiment of the present invention;

[0052] Figure 9 Exploded view showing a fastening system including a detection module according to a second embodiment of the present invention; and

[0053] Figure 10 Perspective view showing a fastening system including a detection module according to a second embodiment of the present invention.

[0054] Figure 11 Schematic cross-sectional view showing a detection module according to a third embodiment of the present invention;

[0055] Figure 12 Schematic cross-sectional view showing a detection module according to a variant of a third embodiment of the present invention;

[0056] Figure 13 Schematic cross-sectional view showing another variant of a detection module according to a third embodiment of the present invention. Detailed Description of the Invention

[0057] In the respective drawings, identical or functionally identical elements are provided with the same reference numerals.

[0058] Figure 1 Schematic cross-sectional view showing a detection module according to a first embodiment of the present invention. Figure 1 The detection module shown is used to monitor the failure of a fastening device, wherein the fastening device includes a fastening rod 1 (which can be, for example, a bolt here) and a fastener 2 and a fastening head 3 (which can be, for example, a nut here) sleeved on the fastening rod 1. The detection module according to the present invention includes:

[0059] An elastically compressible chamber 4, the chamber being arranged to press against a radial plane 7 of the fastener 2 around an axial section 6 of the fastener 2, and a fluid 5 being filled in the chamber 4; and

[0060] A pressure sensor 8, the pressure sensor being in communication with the fluid 5 in the chamber 4 for detecting the fluid pressure.

[0061] Figure 1 The shown fastening device is not fastened, so that the elastically compressible chamber 4 is in its initial state and thus has an initial shape. In this first embodiment, the radial cross-section of the chamber 4 can be circular. Without limitation, the radial cross-section of the chamber 4 can also be elliptical or square. The chamber can be made of, for example, metal, rubber or plastic.

[0062] From Figure 1 It can be seen that the chamber 4 with an annular radial cross-section annularly surrounds the axial section 6 of the fastening rod 1 and the fastener 2 and is placed on the radial plane 7 of the fastener 2. The chamber 4 is filled with a fluid, in particular a gas or a liquid. Preferably, air or oil can be used as the fluid. When the fastening device is locked, the elastically compressible chamber 4 can be compressed and thus pressed against the radial plane 7 of the fastener 2. As a result, the chamber 4 undergoes an overall compressive deformation relative to its initial shape. This compressive deformation of the chamber 4 will cause the volume of the chamber 4 to decrease, which leads to an increase in the pressure of the fluid 5 therein. When the fastening device fails, the chamber 4 can restore its initial shape based on its elasticity, which causes the volume of the chamber 4 to become larger again, resulting in a decrease in the pressure of the fluid 5 therein. Thus, by detecting the change in the fluid pressure with the pressure sensor 8, it can be determined whether the fastening device has failed. In order to reduce the volume of the chamber 4 relative to the initial volume when the fastening device is locked, the axial length H of the chamber 4 in the initial state is greater than the length A of the axial section 6 of the fastener 2.

[0063] In addition, Figure 1 Fig. shows a fastening system according to an embodiment of the present invention. Here, the fastening system not only includes the detection module as described above, but also includes a fastening device, wherein the fastening device includes a fastening rod 1 and a fastener 2 and a fastening head 3 sleeved on the fastening rod 1. The fastening system can be applied to construction engineering, pipeline engineering, mechanical engineering, electrical engineering, etc., for fastening different components together or anchoring components on an installation surface provided by a building structure, such as concrete. The fastening rod 1 can not only include, for example Figure 1 the bolts shown, but also studs, screws, self-tapping screws, wood screws, pins, rivets, welding studs, etc. Here, the bolts can in particular include ordinary bolts, high-strength bolts, anchor bolts, expansion bolts, chemical anchor bolts, stud nails, etc. The fastening head 3 can not only be, for example Figure 1 the nuts shown, but also nuts, etc.

[0064] In Figure 1 the first embodiment shown, the fastener 2 that provides the possibility of surrounding and supporting the chamber 4 can be configured as a one-piece. The fastener 2 can have an L-shaped radial cross-section, that is, it can generally have a shape similar to a flange sleeve or a sleeve with a flange. When fastening with the fastening device, the fastener 2 is sleeved on the fastening rod 1 and the fastener 2 is locked with the component or the installation surface to be fastened by the fastening head 3.

[0065] In particular, it should be mentioned that in the detection module and fastening system according to the present invention, the fastening device, namely its fastening rod 1, fastener 2 and fastening head 3, can all be provided as standard parts conventional in the manufacturing industry. However, in order to adapt to special specification requirements, it is also possible to consider manufacturing the individual components of the fastening device by conventional machining, with almost no high requirements for machining accuracy.

[0066] Figure 2 Fig. shows a schematic top view of the detection module according to the first embodiment of the present invention. It can be seen here the general layout of the detection module on the fastener 2.

[0067] It can be clearly seen from the figure that the chamber 4 of the detection module and the pressure sensor 8 are configured as a split type, and these two are separately arranged on the fastener 2 in the shape of a same-side rounded rectangle in the top view. The left side of the fastener 2 has a semi-circular shape, and in the center of the semi-circle is the upwardly protruding axial section 6 of the fastener 2 (see Figure 1 ). The fastening rod 1 is inserted into the hole in the middle of the axial section 6. The annular chamber in the top view is sleeved on the outer periphery of the axial section 6 of the fastener 2 and supported on the radial plane 7 of the fastener 2 extending in the radial direction with respect to the fastening rod 1. The right side of the fastener 2 has a rectangular shape, and the circuit board 9 also configured as a rectangle is arranged at this end of the fastener 2. This means that the circuit board 9 and the chamber 4 are separated from each other. A pressure sensor 8 for detecting the fluid pressure is provided on the circuit board 9.

[0068] In order to achieve miniaturization of the detection module, it is particularly advantageous to use a MEMS pressure sensor in the present invention.

[0069] In order to make the detection module suitable for an installation environment with drastic temperature changes, it is preferred to be provided with a temperature compensation device for the pressure sensor to reduce or avoid the influence on the detection module caused by the pressure fluctuation due to temperature changes.

[0070] In Figure 1 and 2 Fig. also shows a way of realizing the fluid communication between the pressure sensor 8 and the chamber 4. Here, the chamber 4 is connected to the pressure sensor 8 via the connecting pipe 10. Thus, the pressure of the fluid 5 can also be well detected from the end of the connecting pipe 10 located on the pressure sensor 8.

[0071] In Figure 1 and 2Only the pressure sensor 8 is shown on the circuit board 9 as shown. For the sake of clarity, other electronic components on the circuit board 9 are omitted. On the circuit board 9, various functional units for monitoring the failure of the fastening device can also be provided, such as a signal processing unit, an alarm unit, a communication unit, a power supply unit, an energy harvesting unit, and / or a wake-up unit, etc. The signal processing unit can be, for example, signal-connected to the pressure sensor 8 to analyze and process the pressure signal of the pressure sensor and determine the failure of the fastening device when a fluid pressure change is determined. The signal processing unit can, for example, implement a comparison of the current pressure with the initial pressure when the fastening device is tightened, so as to determine the failure of the fastening device when the pressure decreases, especially when the decrease exceeds a predetermined threshold. Optionally, when the failure of the fastening device is determined, the alarm unit can warn of the failure in the form of a sound and / or light alarm. Optionally, the failure can also be notified to the outside through the communication unit, preferably a wireless communication unit. In order to provide the detection module with the electrical energy required for its operation, a power supply unit and / or an energy harvesting unit can be provided, wherein the power supply unit is preferably powered by a dry battery or a storage battery, and the energy harvesting unit is preferably a solar harvesting unit, a wind energy harvesting unit, a thermal energy harvesting unit, a fluid kinetic energy harvesting unit, or an electromagnetic energy harvesting unit. In order to save electrical energy, it is particularly advantageous that the detection module can also be preferably activated intermittently or in response to an external radio frequency signal by the wake-up unit.

[0072] Figure 3 Fig. shows a schematic cross-sectional view of the detection module according to the first embodiment of the present invention when the fastening device is tightened. In Figure 3 which, as Figure 1 and 2 shown, the detection module is fastened to the mounting surface 11 together with the fastening device. Here, the mounting surface 11 can refer to the surface of a building structure, such as the walls, columns, beams, etc. of a tunnel, a bridge, a building, etc.; the surface of a mechanical equipment component; the fastening surface of a pipe flange, etc. In the mounting surface 11, a hole for receiving the fastening rod 1 can be preset, or a hole can be drilled in the mounting surface 11 by means of the fastening rod 1, such as a self-tapping screw.

[0073] In Figure 3 the tightened state of the fastening device shown, the fastening rod 1, here a bolt, is inserted into the hole in the mounting surface 11. The fastener 2 is tightened with the mounting surface 11 by means of the fastening head 3, here a nut. In this tightened state, the fastener 2 abuts against the mounting surface 11, which causes the elastically compressible chamber 4 to be pressed by the mounting surface 11 against the radial plane 7 of the fastener 2, so that the axial length H' of the chamber 4 compressed at this time is shortened from the axial length H in the initial state to be equal to the length A of the axial section 6 of the fastener 2. As Figure 3 can be seen, the radial cross-sectional shape of the chamber 4 changes from Figure 1The shown ring is flattened into an elliptical ring. Such a compressive deformation will cause the volume of chamber 4 to decrease correspondingly, thereby resulting in an increase in the pressure of the fluid 5 therein. The fluid pressure when the fastening device is locked can be stored as a reference pressure in the signal processing unit during the monitoring of the fastening device for subsequent comparison with the correspondingly detected pressure.

[0074] It can be seen particularly well from Figure 3 that in the fastening system, only the fastening rod 1, the fastener 2, and the fastening head 3 bear the mechanical fastening force, and the force flow of this fastening force is not applied to the detection module, that is, the chamber 4 or the pressure sensor 8. Therefore, the detection module of the present invention does not need to bear the fastening force of the fastening device as a whole. At the same time, the axial section 6 of the fastener 2 provides an axial stop for the chamber 4, thereby limiting the maximum compression degree of the chamber 4, and thus ensuring that the chamber 4 will not be overloaded due to the fastening force of the fastening device when the fastening device is locked.

[0075] Figure 4 A schematic cross-sectional view showing the detection module according to the first embodiment of the present invention when the fastening device fails is shown. Relative to Figure 3 the shown situation, the fastening device fails and loosens, causing the positions of the fastener 2 and the fastening head 3 to drop. Here, the failure of the fastening device may be caused by the loosening of the fastening device itself, slipping out of the thread, creep elongation, and material deformation of the mounting surface fastened by the fastening device. At this time, the separation of the fastener 2 from the mounting surface 11 creates space for the chamber 4 of the detection module to restore its initial shape. In Figure 4 , the radial cross-section of the chamber 4 restores from Figure 3 the shown elliptical ring to a nearly circular ring. The chamber 4 elongates from the compressed axial length H' to the partially restored axial length H'' in the axial dimension. Such a shape restoration makes the volume of the chamber 4 increase, thereby causing the pressure of the fluid 5 therein to decrease relative to Figure 3 the situation in. Thus, by detecting the pressure change of the fluid 5 in the chamber 4 with the pressure sensor 8, it can be monitored whether the fastening device fails. In the present invention, the stress or strain in the fastening device is not directly detected, but the reliable monitoring of the failure of the fastening device is achieved by indirectly detecting the pressure of the fluid 5 in the chamber 4.

[0076] The invention also relates to a method for monitoring the failure of a fastening device by means of a detection module according to the invention. Here, the detection module can be installed in the fastening device, for example, arranged in the fastening device as shown in the respective figures of the specification, and the failure of the fastening device can be monitored by detecting the pressure change of the fluid 5 by means of the pressure sensor 8. Here, the fluid pressure when the fastening device is locked can be used as the reference pressure in the monitoring of the fastening device. During the monitoring of the fastening device, the correspondingly detected pressure is compared with this reference pressure. Once the pressure sensor 8 detects a pressure drop relative to the reference pressure, in particular a pressure drop exceeding a predetermined threshold value, the failure of the fastening device can be determined accordingly.

[0077] Figure 5 Shows a schematic top view of a detection module according to a variant of the first embodiment of the invention. The difference between this variant and Figure 2 that shown is that the chamber 4 is configured as a sector-shaped ring in the top view. Here, the chamber 4 only partially surrounds, rather than completely encloses, the axial section 6 of the fastener 2. Here, the chamber 4 and the connecting pipe 10 are integrally configured as a question mark shape.

[0078] Figure 6 Shows a schematic top view of another variant of the detection module according to the first embodiment of the invention. In this variant, the chamber 4 is configured as a quadrilateral with a central hole in the top view. Figure 7 Shows a schematic cross-sectional view of a detection module according to the second embodiment of the invention. Also shown in Figures 7 to 10 is the fastening device monitored by means of the detection module. The fastening device also includes a fastening rod 1 (which can be, for example, a bolt here) and a fastener 2 and a fastening head 3 (which can be, for example, a nut here) sleeved on the fastening rod 1. Different from Figures 1 to 4 the integral fastener shown, the fastener 2 in Figures 7 to 10 is configured as a split type. As Figure 7 shown, the fastener 2 can be composed of a straight sleeve 22 and a gasket 21. One end of the straight sleeve 22 abuts against the gasket 21, so that as a whole, it also forms a radial cross-section similar to the L-shaped in the first embodiment, and can also provide an axial stop and a radial support for the chamber 4.

[0079] In Figures 7 to 10 for clarity, the mounting surface 11 or component to be fastened is not shown in Figures 7 to 10 In order to show the fastening state of the fastening device, another gasket 23 is arranged on the upper side of the chamber 4, and the other gasket 23 is tightened with the fastener 2 and the fastening head 3 by means of another fastening head 3'. It should be noted in this regard that another gasket 23 is also often placed as a component in the fastening device between the fastener 2 and the mounting surface 11 or component to be fastened.

[0080] In the second embodiment, the detection module also includes: an elastically compressible chamber 4, which is arranged to press against the radial plane 7 of the fastener 2 around the axial section 6 of the fastener 2, and a fluid 5 is filled in the chamber 4; and a pressure sensor 8, which is in communication with the fluid 5 in the chamber 4 for detecting the fluid pressure.

[0081] Different from the split structure of the first embodiment, in the detection module according to the second embodiment, the circuit board 9 together with its pressure sensor 8 can be integrated with the chamber 4.

[0082] To achieve the integration that needs to be sealed here, it is particularly advantageously provided that the compartment 12 communicating with the chamber 4 is sealed by means of the potting part 15 on the circuit board 9. Here, the compartment 12 is arranged on one side of the chamber 4. The compartment 12 communicates with the chamber 4 through a hole 17. It goes without saying that in order to enable the pressure sensor 8 on the circuit board 9 to detect the pressure of the fluid 5, the pressure sensor 8 should be arranged on the side of the circuit board 9 facing the hole 17, and the other side of the circuit board 9 is filled by means of the potting part 15 to seal the compartment 12. In Figure 7 the signal processing unit 13 and the power supply unit 16 are also schematically shown on the circuit board 9.

[0083] As Figure 7 shown, the detection module according to the second embodiment also shows another shape of the chamber 4. Here, the radial cross-section of the chamber 4 is generally square-shaped. This means that the chamber 4 is configured to be flat on its two axial end sides (i.e., on the opposite end sides that are respectively in contact with the gasket 21 and another gasket 23). Such a shape is beneficial for the shape of the chamber 4 to follow the change in the distance between the gasket 21 and another gasket 23, and more volume change can be generated when the shape of the chamber 4 changes, thereby improving the responsiveness achieved in the detection. In this embodiment, when the fastening device is locked, the chamber can be deformed only in part of the direction (here the axial direction), that is, only the axial length is shortened while the radial area remains unchanged.

[0084] In Figure 7 the shown chamber 4 also shows another particularly advantageous design: the axial side wall of the chamber 4 can be configured with one or more corrugations or wrinkles. This can be understood as that one or more corrugations or wrinkles can be formed on the outer circumference and / or inner circumference of the chamber 4. As shown in reference Figure 7In the second embodiment shown, corrugations recessed into the interior of chamber 4 are provided on both the inner and outer axial sidewalls of chamber 4. On the one hand, this can promote the elastic compressibility of chamber 4 in the axial direction. On the other hand, it can define the deformation direction of chamber 4 and thereby reduce its expansion in the radial direction, which in turn helps to increase the pressure change of fluid 5 when the fastening device fails.

[0085] In addition, Figure 7 Another particularly advantageous design is also shown in the second embodiment shown: a wave washer 24 is supported between the fastener 2 and another gasket 23. Without being limited to the shown situation, it is also possible to consider using an elastic washer instead of the wave washer 24; or the wave washer 24 or the elastic washer can be arranged between the fastener and the mounting surface 11 or the component to be fastened. By means of the elastic washer or the wave washer 24, it is particularly advantageous to reliably push open another gasket 24 when the fastening device fails, or to separate the fastening device from the mounting surface 11 or the component to be fastened, so as to move the fastener 2 away from the mounting surface 11 or another gasket 23, thereby creating space for the chamber 4 of the detection module to return to its initial shape, enabling the detection module to particularly reliably monitor failures caused by loosening, thread stripping, creep elongation of the fastening device itself, and material deformation of the mounting surface 11 fastened by the fastening device.

[0086] Alternatively or additionally, it is also possible to consider arranging a spring compressed in the axial direction in the chamber 4, so as to assist the chamber 4 to return to its initial shape in the case of the failure of the fastening device, that is, to push open another gasket 23 or separate the fastening device from the mounting surface 11 by the elastic force of the spring. This can also achieve reliable monitoring of the above-mentioned various failure modes.

[0087] Figure 8 A cutaway perspective view of the detection module according to the second embodiment of the present invention is shown. In this perspective view, the three-dimensional structure of the detection module and the fastening device and their positional cooperation with each other are shown in more detail. It can be well seen from this figure that the chamber 4 surrounds the axial section of the fastener 2, here the straight sleeve 22 of the fastener 2, and the chamber 4 can be pressed against the radial plane of the fastener 2, here the gasket 21 of the fastener 2. In Figure 8 In the fastened state of the shown fastening device, the chamber 4 is clamped between the gasket 21 and another gasket 23 by the fastening head 3 and another fastening head 3', and the upper and lower end sides of the chamber 4 are in surface contact with another gasket 23 and the gasket 21 respectively, so that the shape of the chamber 4 can well follow the position changes of the gasket 21 and / or another gasket 23.

[0088] The corrugations on the axial sidewall of chamber 4 are in Figure 8It is shown as a concave groove 25 on the outer circumferential edge of the chamber 4 and a concave groove 26 on the inner circumferential edge that also recesses into the interior of the chamber 4.

[0089] On an outer peripheral section of the chamber 4, there is connected a compartment 12 for accommodating the circuit board 9. The chamber 4 communicates with the compartment 12 through a hole 17, so that the pressure sensor 8 arranged on the lower side of the circuit board 9 can detect the pressure of the fluid 5 filled in the chamber 4 and the compartment 12. In order to fluid-tightly seal the chamber 4 and the compartment 12, potting is performed on the upper side of the circuit board 9, and the potted part 15 is tightly connected to the wall of the compartment 12.

[0090] Figure 9 An exploded view of a fastening system including a detection module according to the second embodiment of the present invention is shown. The shown fastening system includes the fastening device and the detection module DM as shown before. In this figure, the overall shape of the detection module DM is particularly shown. It can be seen that the detection module DM is generally similar to a key shape, which includes an annular chamber 4 and a cuboid-shaped compartment 12 formed on one of its outer peripheral sections. Here, such an integrated structure is particularly beneficial for the assembly operation of the detection module DM on the fastening device. Here, in order to monitor the fastening device, it is only necessary to pass the detection module DM through the fastening rod 1, fit it on the axial section 6 provided by the straight sleeve 22 of the fastener 2, and place it on the radial plane 7 provided by the gasket 21 of the fastener 2. Optionally, a wave washer 24 can be installed on one end of the straight sleeve 22. Then another gasket 23 is fitted on the fastening rod 1, and finally another fastening head 3' is tightened on the another gasket 23.

[0091] Figure 10 A perspective view of a fastening system including a detection module according to the second embodiment of the present invention is shown. This figure can be understood as the fastening system after the Figure 9 shown parts are assembled together. In Figure 10 it is particularly shown that the detection module DM is configured to be airtight on most of its outer surfaces, and only a rectangular opening 27 is provided in the area of the compartment 12 of the detection module DM. The opening 27 is adapted to the size of the circuit board 9 to be placed therein. In order to airtight the compartment 12 and the chamber 4, potting can be performed on the upper side of the circuit board 9 through the opening 27.

[0092] It is also conceivable that the detection module DM can be connected to the fastener 2, such as the straight sleeve 22, the gasket 21 and / or another gasket 23. By such a connection, the assembly of the detection module can be further simplified, and damage to the detection module during delivery, transportation or assembly can be avoided.

[0093] Figure 11A schematic cross-sectional view of a detection module according to a third embodiment of the present invention is shown. In the third embodiment, the detection module also includes: an elastically compressible chamber 4, which is arranged to press against a radial plane 7 of a fastener 2 around an axial section 6 of the fastener 2, and a fluid 5 is filled in the chamber 4; and a pressure sensor 8, which is in communication with the fluid 5 in the chamber 4 for detecting the fluid pressure.

[0094] Different from the first and second embodiments, the radial cross-section of the elastically compressible chamber 4 is configured as a square. The radial top surface of the chamber 4 is configured as an elastic surface 28, while the remaining part 30 of the chamber 4 can be configured to be relatively rigid or completely rigid. In order to make the elastic surface 28 recess into the interior of the chamber 4 when the fastening device is tightened, so that the volume of the chamber 4 decreases, a protrusion 29 is formed on another gasket 23 opposite to the radial top surface of the chamber 4. When the fastening device is tightened, the other gasket 23 presses down on the corrugated gasket 24. Then, the protrusion 29 moves downward and causes the elastic surface 28 to recess into the interior of the chamber 4, and thus the chamber 4 as a whole presses against the fastener 2. The decrease in the volume of the chamber 4 causes the pressure of the fluid 5 in the chamber 4 to rise, which can be detected by the pressure sensor 8 via the connecting pipe 10. Once the fastening device fails, the other gasket 23 will be pushed open by the corrugated gasket 24, so that the position of the protrusion 29 on the other gasket 23 rises accordingly. Then, at least part of the elastic surface 28 of the chamber 4 resumes its original flat shape, which causes the volume of the chamber 4 to increase, and the pressure of the fluid 5 therein decreases accordingly. Therefore, when the pressure sensor 8 detects a decrease in the pressure of the fluid 5, it can be determined that the fastening device has failed. It goes without saying that in order to deform the elastic surface 28, the protrusion 29 on the other gasket 23 should be smaller than the inner diameter of the radial cross-section of the chamber 4.

[0095] In this third embodiment, the chamber 4 can be made of different materials such as metal, rubber and plastic. For example, the remaining part 30 of the chamber 4 is made of metal, while the elastic surface 28 is made of rubber. The different materials can preferably be connected by pressing, welding, especially ultrasonic welding or fusion welding, two-color injection molding or insert injection molding.

[0096] Figure 12 A schematic cross-sectional view of a detection module according to a variant of the third embodiment of the present invention is shown. The difference between this variant and Figure 12 the third embodiment shown is only that the radial bottom surface of the chamber 4 with a square radial cross-section is configured as an elastic surface 28, and the protrusion 29 for deforming the elastic surface 28 is formed on the fastener 2.

[0097] When the fastening device is locked, another gasket 23 presses the corrugated gasket 24 downward. Then, the chamber 4 presses against the fastener 2 as a whole, which causes the elastic surface 28 of the chamber 4 to press against the protrusion 29 and recess into the interior of the chamber 4. As a result, the volume of the chamber 4 shrinks, and the pressure of the fluid 5 in the chamber 4 rises, which can be detected by the pressure sensor 8 via the connecting pipe 10. Once the fastening device fails, the other gasket 23 will be pushed open by the corrugated gasket 24, and the chamber 4 can then at least partially resume its original flat shape. This causes the position of the chamber 4 to rise accordingly, which increases the volume of the chamber 4 and decreases the pressure of the fluid 5 therein. Therefore, it can also be determined that the fastening device has failed when the pressure sensor 8 detects a decrease in the pressure of the fluid 5.

[0098] In this variant, in order to ensure that the elastic surface 28 of the chamber 4 is reliably located above the protrusion 29, it is particularly preferably possible to connect the elastic surface 28 to the fastener 2, i.e., the protrusion 29.

[0099] Figure 13 A schematic cross-sectional view of a detection module showing another variant according to the third embodiment of the present invention is shown. The difference between this variant and Figure 11 the third embodiment shown is that the remaining rigid part 30 of the chamber 4 is integrated with the fastener 2, here a fastener 2 with an L-shaped radial cross-section. As Figure 13 shown, the axial side wall inside the radial direction of the chamber 4 and the axial section 6 of the fastener 2 can be constructed integrally, and the axial side wall outside the radial direction of the chamber 4 can be a strip 31 extending from the radial plane 7 of the fastener 2, while the radial bottom surface of the chamber 4 can be constructed integrally with the radial plane 7 of the fastener 2. Figure 13 In particular, it is shown that in order to form the axial side wall inside the radial direction of the chamber 4, a shoulder 32 is machined on the axial section 6 of the fastener 2. The axial position of this shoulder 32 is flush with the strip 31 in order to connect, such as by ultrasonic welding or insert injection molding, the elastic surface 28 of the chamber 4 to both of them, thereby forming an elastically compressible chamber 4.

[0100] With Figure 11Similar to the third embodiment shown, when the fastening device is locked, another gasket 23 presses down on the corrugated gasket 24. Thus, the protrusion 29 moves downward and causes the elastic surface 28 to indent into the interior of the chamber 4. At this time, the pressure exerted by the protrusion 29 on the elastic surface 28 is transmitted to the strip 31 and the shoulder 32 through the elastic surface 28 on the one hand and is partially transmitted to the radial bottom surface of the chamber 4 through the fluid 5 in the chamber 4 on the other hand. Thereby, the chamber 4 integrated with the fastener 2 is also regarded as pressing against the radial plane 6 of the fastener 2. At this time, the reduction in the volume of the chamber 4 causes the pressure of the fluid 5 in the chamber 4 to rise, which can be detected by the pressure sensor 8 via the connecting pipe 10. Once the fastening device fails, the other gasket 23 will be pushed open by the corrugated gasket 24, causing the position of the protrusion 29 on the other gasket 23 to rise accordingly. Thus, the elastic surface 28 of the chamber 4 at least partially resumes its original flat shape, which causes the volume of the chamber 4 to increase and the pressure of the fluid 5 therein to decrease accordingly. Therefore, when the pressure sensor 8 detects a decrease in the pressure of the fluid 5, it can be determined that the fastening device has failed.

[0101] Particularly advantageous in this variant is that the remaining part 30 of the chamber 4 can be manufactured with the fastener 2 in one process. This can not only reduce the number of components of the detection module and the fastening system but also effectively simplify the assembly.

[0102] The present invention is not limited to the embodiments shown but includes or extends to all technical equivalents that may fall within the scope of the appended claims. The positional descriptions selected in the specification, such as above, below, left, right, etc., refer to the direct description and the drawings shown and can be transferred to new positions according to meaning when the position changes.

[0103] The features disclosed in the present invention are important for the implementation of the embodiments not only individually but also in any combination and can be implemented.

[0104] It should be understood that the language used in the specification is only for describing specific embodiments and is not intended to limit the present disclosure. All terms used in the specification (including technical terms and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. For the sake of brevity and / or clarity, well-known functions or structures may not be described in detail.

[0105] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes, and decorations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention all fall within the protection scope of the technical solutions of the present invention.

Claims

1. A detection module for monitoring the failure of a fastening device, wherein: The fastening device comprises a fastening rod (1), a fastening piece (2) and a fastening head (3) sleeved on the fastening rod (1), Characterized in that the detection module comprises: an elastically compressible chamber (4) arranged to be pressed against a radial plane of the fastener (2) around an axial section of the fastener, the chamber (4) being filled with a fluid (5); and A pressure sensor (8) is connected to the fluid (5) in the chamber (4) to detect the fluid pressure.

2. The detection module according to claim 1, characterized in that: The fluid is a gas or a liquid, in particular, the gas is air and the liquid is oil.

3. The detection module according to claim 1 or 2, characterized in that: The volume of the chamber (4) is reduced relative to the initial volume when the fastening device is locked, and is at least partially restored when the fastening device fails.

4. The detection module according to claim 3, characterized in that: When the fastening device is tightened, the chamber is deformed as a whole, in partial directions or on at least one wall.

5. The detection module according to any one of claims 1 to 4, characterized in that: The radial cross-section of the chamber (4) is roughly in the shape of a circular ring, an elliptical ring or a square frame, and the axial side wall of the chamber (4) is preferably constructed with one or more corrugations or folds.

6. The detection module according to claim 5, characterized in that: The radial top surface and / or the radial bottom surface of the chamber with a square frame shape in radial cross section are configured as elastic surfaces (28), wherein the remaining part (30) of the chamber with a square frame shape in radial cross section is in particular configured to be rigid, and the remaining part (30) is preferably integrated with the fastening element (2).

7. The detection module according to any one of claims 1 to 6, characterized in that: A spring compressed in an axial direction is arranged in the chamber (4).

8. The detection module according to any one of claims 1 to 7, characterized in that: The chamber is made of metal, rubber and / or plastic, wherein different materials among metal, rubber and plastic are preferably connected by pressing, welding, two-color injection molding or insert injection molding.

9. The detection module according to any one of claims 1 to 8, characterized in that: The pressure sensor (4) is arranged on a circuit board (9).

10. The detection module according to claim 9, characterized in that: The circuit board (9) and the chamber (4) are separated from each other, and the chamber (4) is connected to the pressure sensor (8) via a connecting pipe (10).

11. The detection module according to claim 9, characterized in that: The circuit board (9) together with its pressure sensor (8) is integrated with the chamber (4).

12. The detection module according to claim 11, characterized in that: The compartment (12) in communication with the chamber (4) is sealed by means of a glue potting portion (15) on the circuit board (9).

13. The detection module according to any one of claims 1 to 12, characterized in that: One or more of the following is also provided on the circuit board (9): A signal processing unit (13) connected to the pressure sensor (8) for analyzing and processing the pressure signal of the pressure sensor and determining failure of the fastening device when a change in fluid pressure is determined; an alarm unit, in particular an acoustic and / or light alarm unit; a communication unit, preferably a wireless communication unit; A power supply unit (16), which is preferably powered by a dry cell or a storage battery; An energy collection unit, wherein the energy collection unit is preferably a solar energy collection unit, a wind energy collection unit, a thermal energy collection unit, a fluid kinetic energy collection unit or an electromagnetic energy collection unit; A wake-up unit, wherein the wake-up unit preferably activates the detection module intermittently or in response to an external radio frequency signal.

14. The detection module according to any one of claims 1 to 13, characterized in that: The pressure sensor (8) is a MEMS pressure sensor; and / or the pressure sensor (8) is equipped with a temperature compensation device.

15. Method for monitoring fastening device failure using a detection module according to any one of claims 1 to 14.

16. A fastening system, characterized in that The fastening system comprises a fastening device and a detection module according to any one of claims 1 to 14, wherein the fastening device comprises a fastening rod (1) and a fastener (2) and a fastening head (3) sleeved on the fastening rod (1).

17. The fastening system according to claim 16, characterized in that The radial cross section of the fastener (2) is L-shaped; or the fastener (2) is composed of a straight sleeve (22) and a gasket (21).

18. The fastening system according to claim 17, characterized in that The detection module (DM) is assembled between the mounting surface (12) fastened by the fastening device and the fastener; or the detection module (DM) is assembled between the fastener (2) and another gasket (23).

19. The fastening system according to claim 18, characterized in that An elastic washer or a corrugated washer (24) is supported between the fastener (2) and the mounting surface (1) or the other washer (23).

20. The fastening system according to claim 18 or 19, characterized in that The fastener (2) and / or the further washer (23) are configured with a projection.

21. Fastening system according to any one of claims 18 to 20, characterized in that The detection module (DM) can be connected to the fastener (2) and / or the other gasket (23).

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